/* This file is part of the Palabos library.
 *
 * The Palabos softare is developed since 2011 by FlowKit-Numeca Group Sarl
 * (Switzerland) and the University of Geneva (Switzerland), which jointly
 * own the IP rights for most of the code base. Since October 2019, the
 * Palabos project is maintained by the University of Geneva and accepts
 * source code contributions from the community.
 *
 * Contact:
 * Jonas Latt
 * Computer Science Department
 * University of Geneva
 * 7 Route de Drize
 * 1227 Carouge, Switzerland
 * jonas.latt@unige.ch
 *
 * The most recent release of Palabos can be downloaded at
 * <https://palabos.unige.ch/>
 *
 * The library Palabos is free software: you can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * The library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <cmath>
#include <fstream>
#include <iostream>
#include <vector>

#include "io/parallelIO.h"
#include "palabos3D.h"
#include "palabos3D.hh"

using namespace plb;
using namespace std;

typedef double T;
#define DESCRIPTOR descriptors::D3Q19Descriptor

void cavitySetup(
    MultiBlockLattice3D<T, DESCRIPTOR> &lattice, IncomprFlowParam<T> const &parameters,
    OnLatticeBoundaryCondition3D<T, DESCRIPTOR> &boundaryCondition)
{
    const plint nx = parameters.getNx();
    const plint ny = parameters.getNy();
    const plint nz = parameters.getNz();
    Box3D topLid = Box3D(0, nx - 1, ny - 1, ny - 1, 0, nz - 1);
    Box3D everythingButTopLid = Box3D(0, nx - 1, 0, ny - 2, 0, nz - 1);

    boundaryCondition.setVelocityConditionOnBlockBoundaries(lattice);

    T u = std::sqrt((T)2) / (T)2 * parameters.getLatticeU();
    initializeAtEquilibrium(lattice, everythingButTopLid, (T)1., Array<T, 3>((T)0., (T)0., (T)0.));
    initializeAtEquilibrium(lattice, topLid, (T)1., Array<T, 3>(u, (T)0., u));
    setBoundaryVelocity(lattice, topLid, Array<T, 3>(u, (T)0., u));

    lattice.initialize();
}

template <class BlockLatticeT>
void writeGifs(BlockLatticeT &lattice, IncomprFlowParam<T> const &parameters, int iter)
{
    const plint imSize = 600;
    const plint nx = parameters.getNx();
    const plint ny = parameters.getNy();
    const plint nz = parameters.getNz();
    const plint zComponent = 2;

    Box3D slice(0, nx - 1, 0, ny - 1, nz / 2, nz / 2);
    ImageWriter<T> imageWriter("leeloo");

    imageWriter.writeScaledGif(
        createFileName("uz", iter, 6), *computeVelocityComponent(lattice, slice, zComponent),
        imSize, imSize);
}

int main(int argc, char *argv[])
{
    plbInit(&argc, &argv);
    global::directories().setOutputDir("./tmp/");

    IncomprFlowParam<T> parameters(
        (T)1e-2,  // uMax
        (T)100.,  // Re
        100,      // N
        1.,       // lx
        1.,       // ly
        1.        // lz
    );
    const T logT = (T)1 / (T)200;
    const T imSave = (T)1 / (T)200;
    const T maxT = (T)1;

    writeLogFile(parameters, "3D diagonal cavity");

    // Attention: this program works either in serial, or in parallel when executed
    //   on exactly 3*4*2=24 threads.
    plint envelopeWidth = 1;
    MultiBlockLattice3D<T, DESCRIPTOR> lattice(
        MultiBlockManagement3D(
            createRegularDistribution3D(
                parameters.getNx(), parameters.getNy(), parameters.getNz(), 3, 4, 2),
            defaultMultiBlockPolicy3D().getThreadAttribution(), envelopeWidth),
        defaultMultiBlockPolicy3D().getBlockCommunicator(),
        defaultMultiBlockPolicy3D().getCombinedStatistics(),
        defaultMultiBlockPolicy3D().getMultiCellAccess<T, DESCRIPTOR>(),
        new BGKdynamics<T, DESCRIPTOR>(parameters.getOmega()));

    lattice.periodicity().toggleAll(false);
    lattice.periodicity().toggle(0, true);

    OnLatticeBoundaryCondition3D<T, DESCRIPTOR> *boundaryCondition
        //= createInterpBoundaryCondition3D<T,DESCRIPTOR>();
        = createLocalBoundaryCondition3D<T, DESCRIPTOR>();

    cavitySetup(lattice, parameters, *boundaryCondition);

    T previousIterationTime = T();

    // Main loop over time iterations.
    for (plint iT = 0; iT < parameters.nStep(maxT); ++iT) {
        global::timer("mainLoop").restart();

        if (iT % parameters.nStep(logT) == 0) {
            pcout << "step " << iT << "; t=" << iT * parameters.getDeltaT();
        }

        if (iT % parameters.nStep(imSave) == 0) {
            pcout << "Writing Gif ..." << endl;
            writeGifs(lattice, parameters, iT);
        }

        previousIterationTime = global::timer("mainLoop").stop();

        // Lattice Boltzmann iteration step.
        lattice.collideAndStream();

        if (iT % parameters.nStep(logT) == 0) {
            pcout << "; av energy=" << setprecision(10) << getStoredAverageEnergy<T>(lattice)
                  << "; av rho=" << setprecision(10) << getStoredAverageDensity<T>(lattice) << endl;
            pcout << "Time spent during previous iteration: " << previousIterationTime << endl;
        }
    }

    delete boundaryCondition;
}
